There has been an increase in demand of pheromone formulations which have a reservoir in which a pheromone substance that is effective for insect pest control is contained, which are secured stably for a long period of time to a predetermined place, for example, in a farm field, and which are adapted to allow the pheromone substance in the reservoir to be released continuously and sustainedly into air. Thus, various proposals associated therewith have been made.
As a bag type pheromone formulations which is capable of being easily attached to a tree or other support, there have been proposed the formulation using a polymer bag in which a slit, having an engaging hole at the tip thereof, is cut from at least one edge of the polymer bag (Japanese Utility Model Application Unexamined Publication Nos. 2-69902 and 2-69903).